Squid Web Proxy up to 2.7.STABLE9/5.9/6.5 HTTP Request Parser X-Forwarded-For recursion

Summaryinfo

A vulnerability classified as critical has been found in Squid Web Proxy up to 2.7.STABLE9/5.9/6.5. Affected is an unknown function of the component HTTP Request Parser. The manipulation of the argument X-Forwarded-For leads to recursion. This vulnerability is listed as CVE-2023-50269. The attack may be initiated remotely. There is no available exploit. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in Squid Web Proxy up to 2.7.STABLE9/5.9/6.5 (Firewall Software). It has been rated as critical. This issue affects some unknown processing of the component HTTP Request Parser. The manipulation of the argument X-Forwarded-For with an unknown input leads to a recursion vulnerability. Using CWE to declare the problem leads to CWE-674. The product does not properly control the amount of recursion that takes place, consuming excessive resources, such as allocated memory or the program stack. Impacted is availability. The summary by CVE is:

Squid is a caching proxy for the Web. Due to an Uncontrolled Recursion bug in versions 2.6 through 2.7.STABLE9, versions 3.1 through 5.9, and versions 6.0.1 through 6.5, Squid may be vulnerable to a Denial of Service attack against HTTP Request parsing. This problem allows a remote client to perform Denial of Service attack by sending a large X-Forwarded-For header when the follow_x_forwarded_for feature is configured. This bug is fixed by Squid version 6.6. In addition, patches addressing this problem for the stable releases can be found in Squid's patch archives.

The weakness was presented 12/14/2023. The advisory is shared at github.com. The identification of this vulnerability is CVE-2023-50269 since 12/05/2023. Technical details are known, but no exploit is available. MITRE ATT&CK project uses the attack technique T1499 for this issue.

The vulnerability scanner Nessus provides a plugin with the ID 235552 (RockyLinux 8 : squid:4 (RLSA-2024:1375)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.6 eliminates this vulnerability. Applying a patch is able to eliminate this problem. The bugfix is ready for download at squid-cache.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the vulnerability database at Tenable (235552). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Type

• Firewall Software

Vendor

• Squid

Name

• Web Proxy

Version

• 2.7.STABLE9
• 5.0
• 5.1
• 5.2
• 5.3
• 5.4
• 5.5
• 5.6
• 5.7
• 5.8
• 5.9
• 6.0
• 6.1
• 6.2
• 6.3
• 6.4
• 6.5

License

• open-source

Website

• Vendor: http://www.squid-cache.org/

CPE 2.3info

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CPE 2.2info

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If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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